The present invention relates to a method for measuring a three-dimensional position of an object to be captured which automatically effects, by a robot, the white balance adjustment and cut-off adjustment of primarily industrial displays (hereinafter referred to as display) and a method for capturing the object located at the three-dimensional position.
In the production process of display devices, the positioning thereof is difficult because of the rotary structure of the display device and the unique shape of the cathode-ray tube, and the positioning of a printed circuit board installed behind the cathode-ray tube is also difficult, and is mostly manually effected.
In order to automatically effect the white balance adjustment and cut-off adjustment of the display device, there have been tried a method of fastening the printed circuit board installed behind the cathode-ray tube with a jig so as to electrically adjust it by an automatic apparatus, and an electrical adjustment method arranged to contact a probe with the printed circuit board with a force controllable robot so as to read the current position, and to obtain the three-dimensional position of the printed circuit board by repeating the operation at six points in total.
However, there have been recently provided many kinds of displays, and therefore, according to the method of fastening the printed circuit board installed behind the cathode-ray tube with a jig by electrically adjusting with an automatic apparatus, the position of the jig has to be changed in accordance with the kinds of displays, and in the case of a display having a rotary structure, it is almost impossible to fix the position of the jig.
Furthermore, in the method of using the force controllable robot, since the force control accuracy of the robot is poor and the printed circuit board is deflected by the contact of a probe, it is difficult to obtain a correct value. Furthermore, because of six points measurement, there is a disadvantage of a long measuring time.
In view of the foregoing, an essential object of the present invention is to provide a practical method for measuring without contact the three-dimensional position of an object such as a printed circuit board by using visual recognition.